Nature Itself Has Destroyed 99% of All Species Since Abiogenesis
The origin of life on Earth (abiogenesis) is one of the great mysteries of science. It seems that the processes of nature have allowed life to arise out of dead materia, to flourish and evolve into complex beings intelligent enough to understand what is happening to them. But nature has also destroyed enormous amounts of species along the way.
The Origin of Life
Did life arise in the oceans or did it come from space? We have no idea. But it could have been here ever since the planet cooled off. If so, simple organic molecules may have begun to form and eventually tie up to form RNA, a molecular candidate long attributed as essential for the origin of life.
The most common scientific hypothesis is that the transition from dead material to living entities on Earth was not a single event, but a process of increasing complexity. This process seems to have taken place at the same time as the young planet was bombarded by thousands of asteroids, comets and space rocks, an event named the lunar cataclysm.
Did life emerge and disappear repeatedly during this period or did it actually arrive during the bombardement? And if so, where did the spacebound organic compounds come from and how were they formed? We currently do not have the answer to the true origin of life, other than that everything is ultimately made from stardust.
Somehow the early life must have gained a foothold on our planet and evolved into more complex and self-replicating structures. This probably happened in volcanically active hydrothermal environments on land and at sea. The favorable conditions on Earth (steady sunlight, organic compounds and water) then allowed life to evolve during billions of years.
The interplay between the new inhabitants and the lifeless planet somehow generated a circle of life, different from any previous chemical or geological processes. The plants breathe out oxygen while the living creatures are breathing in the same atoms. It seems that this interplay has kept the level of oxygen in the atmosphere constant for hundreds of millions of years.
Oxygene has also allowed the ozone layer to regenerate in the stratosphere. The ozone layer protects from ultraviolet light and has allowed life to crawl up on land. There seems to be a self-regulation baked into the process of nature, which assures that equilibrium remains.
The Human Epoch
A new species evolved in eastern Africa a few hundred thousand years ago. The number of beings was small for a long time and its existence was fragile. The new race was not particularly fast or strong but remarkably inventive. Eventually they moved to other regions with new prey and different climates.
They crossed mountains and rivers and spread to other continents. Wherever they go they adapt and push away other creatures, some of them being much bigger, stronger and faster.
The process continued for thousands of years until the new species has spread across the whole planet. At a certain point in time the population, now known as homo sapiens, multiplied in just a few hundred years and clustered in urban areas.
While the unaware life (plants, animals etc) seemed to live in perfect harmony with nature and paving way for its own evolution, the aware life (Homo sapiens) seemed to do everything possible to break this equilibrium.
They devastated forests and rearranged the biosphere, they changed the climate and the chemistry in the oceans. The impact on the planet was so great that a new epoch was invented, Anthropocene — The Human Epoch.
The Extinction of Life
Ever since the first simple organic molecules formed and up to now, nature has created and destroyed enormous amounts of species, long before humans walked the Earth. Some scientists estimate that as much as 99% of all living beings that have ever existed, are now gone.
The biggest driver of extinctions appears to be major changes in Earth’s carbon cycle, caused by huge volcanic eruptions. The volcanoes ejected massive amounts of heat-trapping gases such as carbon dioxide into the atmosphere, enabling runaway global warming and related effects such as ocean acidification and anoxia.
Many of the prehistoric creatures and plants were probably wiped out during one of five big events, often referred to as the Five Extinctions. The last one happened some 66 million years ago when a huge asteroid or comet slammed into Earth. But somehow evolution went on and formed new life forms that could only exist as a result of the previous catastrophes.
New research suggests that our planet is headed for a sixth mass extinction. That there are more species becoming extinct than normal and that the rate is clearly higher. The difference is that this mass extinction is caused by human activity.
But humans are a product of nature, regardless of our unnatural behavior. And without the previous five extinctions, and everything that happened inbetween, we wouldn’t exist and we couldn’t exist.
The Processes of Nature
There are scientific theories that suggest that all life must overcome certain challenges, and at least one hurdle is impossible to clear. Such hurdles could be impact events, volcanic eruptions, gamma-ray bursts, geomagnetics storms, pandemics, long-term climate changes and similar periodic catastrophic events that must be inevitable in the longer perspective.
Some ecosystems in the world (such as the northern forests) have adapted to constantly recurring fires. Natural forest fires may have many positive effects — nutrients, especially nitrogen, are released and reused in the cycle. After a fire, germination is also stimulated and a rejuvenation of the forest landscape takes place — many animals and plants have the opportunity to spread into new habitats.
This natural process has been going on since before humans walked the Earth, while fires in other ecosystems, such as tropical rainforests, are a completely new phenomenon and which only have destructive consequences. So, depending on a number of crucial parameters, you may have rebirth or destruction.
On a cosmic scale, the Human Epoch will pass by as a parenthesis. Our remains and other traces will be pushed down into the core where it melts and becomes part of the bloodstream that will continue for billions of years.
